Power-conserving air-channel propeller for flying-machines



1.1. A. MILLER.

POWER CONSERVING AIR CHANNEL PROPELLER FOR FLYING MACHINES.

' APPLICATION FILED JUNE 28. 19l9.

1,3'38,5 1 6 Patented Apr. 27, 1920.

INVENTOI? M J ATTORNEY JOHN J. A. MILLER, OF DENVER, GOLQRADO.

POWER-CONSEBVING AIR-CHANNEL PRGPELLEE .lUR FLYING-MACHINES.

Specification of Letters Patent.

Patented Apr. 27, men.

Application filed June 28, 1919. Serial No. 367,375.

To all whom it 11mg concern:

Be it known that 1, JOHN J. A. fviILLER, a citizen of the United States of America, residing in the city and county of Denver and State of Colorado, have invented new and useful Power-Conserving Air-Channel Propellers for Flying-\llachines, of which the following is a specification.

This invention relates to improvements in power conserving airchannel propellers for flying machines.

The object of the invention is to provide a propeller of such construction that it cannot slip or fail to engage the air in such manner as to continuously propel the craft upon which it is installed. Further, to provide a propeller having pocketed blades through which the air is forced as the propeller rotates, will not only take hold upon the air, but that they will engage a body of new air upon each rotation of the propeller, thereby accomplishing continuous propulsion, the said propeller, by reason of its construction, being capable of a given rate of speed with fewer rotations per minute than propellers of the usual construction.

These objects are accomplished by the construction illustrated in the accompanying drawings in which,

' Figure 1 is a perspective view of the improved propeller.

Fig. 2 is a side view thereof, partly in section.

Fig. 8 is a top view of a portion of the propeller.

Fig. 1 is a transverse Vertical sectional view of the same on the line 4 l of Fig. 2, the propeller being shown secured upon a shaft.

Fig. 5, is a sectional view similar to Fig. 1, showing a wooden blade having a metal facing, and

Fig. 6 is also a sectional view similar to Fig. 4, but showing one wall of the pocket provided with corrugations.

Referring to the accompanying drawings, the numeral 1, indicates the hub portion of the improved propeller, which is provided with an axial threaded hole 2, which commonly extends partially through the hub, the remainder of the hole being flared and unthreaded, as shown by dotted lines in Fig. 4; but the character of this aperture or the manner of securing the propeller to the engine shaft, form no part of the present inthus insuring that the blades vention, as any approved method of securing the propeller to its shaft, may be employed. As illustrated, however, the outer end portion of the engine shaft 3, is threaded and flared to correspond to the hole in the hub, and the propeller is screwed upon the end of the shaft in a reverse direction to that in. which it turns when in operation.

The shaft has a flange or collar at, against which the propeller is screwed, and a collar 5, is screwed on the outer end of the shaft against the propeller and are secured by nuts which may be held against back rotation in any preferred manner. A nut 7. is screwed on the end of the shaft, against the collar 6. and is held in place by a cotter pin 8. The propeller illustrated is of the true screw type, though the invention is also adaptable to either the radially expanding or the axially expanding types of propeller. The blades 9. of the propeller, are of the required pitch, and in transverse section, they decrease in thickness from their advancing edges to their opposite edges, and each blade is hollow or formed with a slot or pocket 10. which extends through the blade, as shown, the pocket being relatively wide at the entrance 11, and decreasing in width to a narrow outlet 12, thus conforming to the taper of the blade. The ends of the pockets preferably converge from entrance to outlet so that the outlet is of less length than the entrance. This construction of the blades insures their taking hold upon the air, as the air is caught, or pocketed by the blades as the propeller rotates, thus preventing slip or the failure of the blades to engage new air upon each rotation. The pocketed air escapes through the outlet 12. and the pocketing of the air together with its forcible exit through the outlet, exerts a deflecting action upon the blade, which alone, tends to cause a continuous forward feeding of the propeller as the same rotates, the pocket having the same pitch as the blade, but the propelling force exerted by the rush of air through the pockets, is an added force which acts in conjunction with the natural propelling force due to the pitch of the blades. It will thus be seen that the improved propeller combines two separate and distinct, though cooperating propelling properties: namely, that conferred by the pitch of the blades, as in all forms of screw propellers, and that conferred by the pitched pockets in the said blades, which collect or pocket the air, which is forcibly ejected through the out lets in said pockets, causing the deflecting action upon the blades, as above described, the two separate actions being simultaneous, and resulting in a common propelling impulse, of greater drawing or pulling force than is possible with the common type of propeller.

This being the case, a propeller of this construction, would propel an air craft a given distance, with fewer rotations per minute than would a propeller of the common type, thereby effecting a saving of fuel, as well as of mechanical energy.

The propeller may be constructed of materials other than metal, and when wood is employed as represented in Fig. 5, the blades 18. are faced with sheet metal 14. of any suitable character, which is held in place by bolts 15. which extend entirely through the blades, and thus prevent them from splitting or flying apart under the pressure of the pocketed air. In Fig. 6, a slight modification in the character of the pocket is illustrated, one wall of the pocket being stepped or corrugated as shown at 16. to offer a greater resistance to the air, and thereby increase the air gripping power of the blades. While the drawings illustrate a two blade propeller, it will be understood that the invention contemplates a propeller having two or more blades.

Having described my invention, what I claim as new and desire to secure by Letters Patent, is:

l. A wooden propeller having blades provided with air-collecting pockets which extend through the blades on the line of their pitch, a metal facing for said blades and bolts which extend through said facings and blades.

2. A propeller having blades provided with air-collecting pockets which extend through said blades in the direction of their pitch, said pockets having contracted outlets, one wall of each of said pockets having longitudinal corrugations.

3. A propeller comprising a hub and blades extending therefrom which taper from their leading to their following edges, an uninterrupted pocket extending through each blade, the mouth of said pocket being of the full length of the blade, while its sides and ends taper toward the outlet thereof; the pitch of said pockets corresponding to the pitch of the said blades.

In testimony whereof I affix my signature in presence of two witnesses.

JOHN J. A. MILLER. lVitnesses:

Gr. SARGENT ELLIOTT, ADA DWELLE. 

